Global trade of coronavirus hosts: bringing geographically isolated hosts and viruses together risks novel recombination and spillover to humans

Novel pathogenic coronaviruses - such as SARS-CoV and probably SARS-CoV-2 - arise by two coronaviruses co-infecting viruses a single host cell, and then 'swapping' parts of their genome. The result of this swapping (termed homologous recombination) is a novel daughter virus containing components of each parent virus. These viruses then circulate in reservoir animal populations before spillover to humans. Our previous work has identified mammalian and avian hosts susceptible to each coronavirus and hosts biologically susceptible to multiple coronavirus strains (recombination hosts). Here, using a novel ecological network approach, integrating presence, habitat, and behaviour indicating ecological traits of host species, we will build on our previous work to predict contact facilitated sharing of coronaviruses. Combining these predictions with epidemiologically-relevant spatial predictors, will allow us to predict geographical hotspots of coronavirus recombination (Work package 1), and therefore enable specific spatially-targeted surveillance and mitigation efforts. Many coronavirus hosts interact with humans (e.g. through geographic/habitat overlap), or are used by humans as (e.g. pets/food). By enriching our novel network from WP1 with host species utilisation data from open-access sources, we will estimate the in situ likelihood of spillover from our previously identified hosts (Work package 2). Highlighting priority species and geographic hotspots for spillover mitigation efforts. Wild animal trade has been implicated in the spillover of coronaviruses, including SARS-CoV-2, to humans. Trade could also readily facilitate homologous recombination in otherwise geographically isolated hosts and their respective coronaviruses. Utilising global animal trade and usages in our predictive framework will enable us to assess the impact of trade on spillover and recombination risk (Work package 3). Understanding the relative risk of wild host trade will allow insight into avoidable human influence on novel coronavirus generation.